package util;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;

/**
 *
 * @author Tony Shen
 */
public class DateUtils {

    public static Date getMonthStart(String year,String month) throws ParseException {
         String startDateStr = year + "-" + month + "-" +"01";
         SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");
         Date startDate = sdf.parse(startDateStr);
         return startDate;
    }

    // 按照年月返回月的最后一天
    public static int getMonthOfDays(int year, int month) {
        int days = 0;
        if (month != 2) {
            switch (month) {
                case 1:
                case 3:
                case 5:
                case 7:
                case 8:
                case 10:
                case 12:
                    days = 31;
                    break;
                case 4:
                case 6:
                case 9:
                case 11:
                    days = 30;
            }
        } else {
            if (year % 4 == 0 && year % 100 != 0 || year % 400 == 0) {
                days = 29;
            } else {
                days = 28;
            }
        }
        return days;
    }


}
